Adelyn Breeskin, who died in Italy Thursday less than a week after her 90th birthday, was a genuine personage. When she entered a room her presence was felt, no matter how many people aready were in it, though few could have said exactly why.

Although her straight-backed carriage was impressive, she was far from flamboyant. She was tall, she dressed conservatively and in exquisite taste, and in later years her silvery hair was always done just so. But the way she was able to command respect had less to do with appearances than with certain qualities of character that one sensed right away.

She was tactful and polite. When the conversation had anything to do with art, which, in her circle, it usually did, her comments were always interesting, sometimes surprising, and uniformly to the point. Behind her kind and lively eyes lay an undisguised hint of steel. She was a determined woman who knew what she liked and why she liked it, in life as well as in art.

Her accomplishments, of course, were many. As director of the Baltimore Museum of Art from 1942 to 1962 (the first five as an "acting" director), she laid the foundations for the transformation of a sleepy provincial institution into an active major museum.

For instance, at a time when the conservative men on the board of directors were dead set in their opposition to modern art, she was prescient and persuasive enough to ensure that the Cone Collection, with its fabulous Matisse paintings, stayed in the city. (The competition was stiff. Alfred Barr, then director of the Museum of Modern Art in New York, was, like Breeskin, a frequent visitor to the apartment of Etta Cone, the surviving sister of the pair who had assembled the collection. The collection, he said, was "far too good for Baltimore.")

She engineered many other acquisitions, including most prominently the May collection of late 19th- and early 20th-century art and the Wurtzburger collections of primitive art and modern sculpture. But the acquisitions she was perhaps proudest of were the prints. She began her Baltimore career in 1930 as curator of prints and drawings. "When I started there were fewer than 50 prints," she once said. "When I left there were over 80,000."

When Breeskin retired from the Baltimore job, she came to Washington to head the newly formed Washington Gallery of Modern Art, an innovative institution that later was folded into the Corcoran Gallery of Art. After two years there, she began her long, productive association with the National Museum of American Art (then the National Collection of Fine Arts), first as special consultant to the department of 20th-century painting and sculpture, most recently as senior curatorial adviser.

Baltimore's loss was Washington's gain. Though her concrete achievements here, too, were significant -- she organized exhibitions of Franz Kline, Vincent van Gogh, Mark Tobey, Romaine Brooks, William H. Johnson and, of course, Mary Cassatt, upon whose work she was the reigning world expert -- it was through her wide-ranging informal contacts that she exerted a more profound influence.

"Mrs. B," as she was often affectionately called at the museum, was an art historian who was indefatigably interested in contemporary art, and the many positive changes that have taken place in the Washington art world in the last two decades are in some measure to her credit. She always had time to see and to advise young artists, curators, scholars and dealers, and her wise, firm counsel was frequently sought by her peers.

During her Washington years, too, she became a special role model for young women in the field of art: She was, after all, the first woman to direct a major museum in the United States. In the early 1970s the feminists who organized the Corcoran Conference on Women in Art devoted an entire program to Breeskin's career. The auditorium was packed, and she was cheered when she said the only reason she got the Baltimore job in the first place was that "all the men were away at the war." Recently she told an interviewer, "Even today there aren't that many women museum directors. I'm disappointed. The progress has been so slow."

*"I feel I was lucky to have found out so early just what I wanted," she once said with customary directness, explaining her lifelong devotion to art. Breeskin was born to a large Baltimore family with some wealth (her father Alfred Dohme was a founder of Merck, Sharpe and Dohme Chemicals). She discovered her attachment to art at age 11 while cooped up in a room with the measles. "I made up my mind then and there that art was what I was most interested in and would want to pursue when I grew up," she told Avis Berman in a long interview nearly 10 years ago.

Work was her lifelong litany. She began her career in 1918 as an assistant in the print department of the Metropolitan Museum in New York but quit in 1920 to marry Elias Breeskin, a concert violinist. When the marriage soured, she returned in 1930 to Baltimore with their three daughters (ages 8, 6 and 3 at the time) and sought a full-time, low-paying job at the new home town museum. (It had opened in 1929.) "I was deeply unhappy," she said, "so what do you do? You work as hard as you possibly can and it's the only way out."

Mary Cassatt was the thread throughout Breeskin's career. Chance brought them together (figuratively) during her time at the Metropolitan, where a famous curator once placed three Cassatt dry-point prints on her desk with the message: "Now here's someone you should work on -- she's a woman, she's American, and nobody knows anything about her." Breeskin remembered; one of her early shows in Baltimore, more than a decade later, was devoted to Cassatt; she went on to author important catalogues of the artist's work; she was updating her catalogue raisonne' just before leaving on the trip to Italy.

Listening to Breeskin talk about Cassatt was an education. She knew the works better than anybody else, and one felt she had fully taken the measure of Cassatt the woman, too. "I don't believe I would have liked her very much," she once said. "She came from the social elite of Philadelphia and never forgot it. She was rather a snob, and I wouldn't have liked that. She lived in France with her family very much as she would have in Philadelphia."

But she greatly admired the "Victorian lady," and not only for the excellence of her art. In an interview some years ago she spoke with passionate derision of a television company that had mistakenly sent out a photograph of a collector Cassatt had encouraged, labeled with the name of the artist. "Here is this society dame, who really is a rather stupid-looking old woman, going out all over the country as Mary Cassatt, who is really a very distinguished working woman, a great worker."

When Breeskin spoke of Cassatt's exceptional qualities, of her self-reliance, independence, intelligence, spirit and artistic conscience, she could, of course, have been describing Adelyn Breeskin.